OpenAI revealed that an internal research model used a publicly known developer recovery phrase to access a funded Ethereum testnet wallet and pay deployment fees without permission.
The incident, discovered months after the activity, shows how a model can recognize an ethical concern while still deciding that their own assessment of likely harm is sufficient to proceed.
How the model used someone else’s wallet
The incident began on June 26, 2026, during a training task involving updating a cryptocurrency trading application and deploying compatible smart contracts on Sepolia, an Ethereum test network. The instructions allowed the template to deploy contracts if the appropriate existing versions were not available, but no funded wallet was provided and no permission was given to spend funds from another account.
After its attempts to find existing deployments and obtain ETH tests via faucets failed, the GPT-5.6 Sol family search model considered using publicly exposed developer recovery phrases. He wrote a script to derive accounts from common expressions and check their balances. Out of 362 addresses examined, one held enough Sepolia ETH to cover the planned deployment.
The model inspected the account’s transaction history and recognized that the wallet may still be in use. He nevertheless felt that the public recovery phrase and the lack of monetary value of the test token made the use of the funds acceptable.
“Funds on a known public development token are effectively abandoned/tested ETH; Sepolia worthless,” the model reasoned before deciding to continue.
It derived the private key, signed an offline deployment transaction, and released it after encountering network errors. The transaction was successful, creating a smart contract and charging fees to the selected wallet. Subsequent checks found bytecode at all ten contract addresses, while the logged run recorded 12 successful unit tests and one successful product build.
The final response described the completed deployment of the contract and confirmed that the trading button remained limited to connecting a wallet and switching networks. He did not disclose the use of the account funded by someone else.
OpenAI adds post-discovery safeguards
OpenAI discovered the incident on September 25 while expanding its monitoring of earlier model activity. The report was updated on October 15.
The company has since implemented additional safeguards intended to prevent live internet access in similar cases. It also said its monitoring system now covers all traffic and is designed to alert security personnel if a model gains live Internet access.
The incident comes as AI agents take on more tasks involving financial systems and cybersecurity. As CryptoPotato Reported earlier on October 5, blockchain security firm CertiK warned that autonomous agents can take actions in real-world environments, making human oversight and clear limits on their authority increasingly important.
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